William i



(N0 Model.)

I W' I- BU-NKER,

SPRING'ATTAGMNT FOR PLATFORM ROGKING CHAIRS. No.` 297,108. Patented A131222., 1884.

N. Pneus. mwmgnpnen wnsluugwn. u4 c STATES NITE WILLIAM I. BUNKER, OF CHICAGO, ILLINOIS, ASSIGNOR OF ONE-HALF TO JACOB BEIERSDORF, OF SAME PLACE.

SPRING ATTACHMENT FOR PLATFORM ROCKlNG-YCHAIRS.

SPECIFICATION forming part of Letters Patent No. 297,108, dated April 22, 1884.

Application tiled July 27, 1883.

To all whom it may concern:

Be it known that I, WILLIAM I. BUNKER, of Chicago, Illinois, have invented certain new and useful Improvements in Spring Attachments for Platform Rocking-Chairs, of which the following is a specification.

The object of my invention is to provide heavy rocking-chairs with suitable springs, and to this end the invention consists in provid- 1o ing the chair with a double bracket on either side, such bracket having coiled therein two large stiff springs, in making one of said springs of lighter wire than the other, and in providing a lu g on' said bracket to form a pivot or bearing to lessen the friction of the spring.

In the accompanying drawings, Figure l shows my improved 'spring attached to the inner faces of the rocker and base-rail of a platform rocking-chair. Fig. 2 is a vertical 2o sectional view ot' the springs detached; and

Fig. 3 is a broken section of one of the springcoils, showing the lug for lholding the spr-ing vout from the casting, as hereinafter described.

A Aare the castings which hold the springcoils, B B the spring-coils, and C the shoulder or lug on the casting A, which holds the upper and lower coils of the springs away from the face of the castings. Double brackets AA are provided for each side of the chairA and secured 3o totherockerandbase-rail,respectively. These brackets are provided with an annular rib or flange cast on the inside face of the bracket, and provided with a stop at the end of the rib, against which the end coil of the spring rests.

Vithin these brackets are coiled two broad stiff springs, B B, their ends being securely held by the annular rib or flange on brackets A. This double bracket is cast in one piece,

and when provided with two heavy springs 4o will furnish a safe and strong attachment for heavy chairs. No stops or side flanges will 4be required to prevent lateral displacement of the rockers. The springs are coiled into the brackets before the latter are secured to (No model.)

upward and downward than the rear portion, 5o

I find it desirable to construct the rear spring of a somewhat larger wire than the front spring. This permits a longer sweep'of the front ends of the rockers, and by the increased strength given the rear spring prevents the displacement lof the rockers or the liability of the breaking of said spring.

To overcome the friction produced by the rubbing of the end coils of the springs against the brackets when in use, I have reduced the 6o bearing-surface ofsuch end coils on such brackets to a minimum by casting on the inside of the bracket, behind the end coils, a shoulder or lug, (marked Cin the drawings) which lug prevents contact of the springs and brackets, and thus avoids the friction between them and the rasping noise incident thereto.

I claiml. The double brackets A A, having coiled therein the springs B B, as a new manufacture 7o fQr attachment to platform rocking-chairs,substantially as and for the purpose described.

2. In a platform rocking-chair, the combination, with the rocker and base-rail, of the brackets A A and coil-springs B B', one of 75 said springs being constructed of lighter wire than the other, substantially as described, and for the purpose set forth.

3. The combination, in a platform rockingchair, of the brackets A A and coil-wire spring 8o B, said brackets provided with a lug, C, substantially as described, and for the purpose set forth.

VILLIAM I. BUNKER.

Vitnesses:

THOMAS A. BANNING, CHAs. C. LINTHIGUM. 

